Disulfuration and hydrosulfuration of an alkyne at a 1,2-dicarba-closo- dodecaborane-thiolate ligand

The reaction of the dinuclear cobalt compound [(CpCoS₂C ₂B₁₀H₁₀)(CpCoSC₂B₁₀H ₁₁)(n-C₄H₉S)] (1) with HCCC(O)Fc leads to the cobalt-free products (C₂B₁₀H₁₀)(SCHCHCOFc) ₂ (4-6), (S₂C₂B₁₀H ₁₀)(HCCCOFc) (7), and (C₂B₁₀H ₁₁)(SCHCHCOFc) (8, 9). 4-6 are produced by hydrosulfuration of the alkyne at the 1,2-dicarba-closo-dodecaborane-dithiolate ligand with the generated vinyl groups in Z/Z, Z/E and E/E configurations, respectively. In 7, the alkyne is added to 1,2-dicarba-closo-dodecaborane-dithiolate at the two sulfur sites. 8 and 9 are the products of alkyne hydrosulfuration at the 1,2-dicarba-closo-dodecaborane-1-monothiolate ligand with the generated vinyl group in either Z or E configuration. The treatment of 1 with HCCCO ₂Me gives rise to the parallel products (C₂B ₁₀H₁₀)(SCHCHCO₂Me)₂ (10-12) and (C₂B₁₀H₁₁)(SCHCHCO₂Me) (13, 14). All of the new compounds have been characterized by IR, NMR, elemental analysis and mass spectroscopy. The structures of compounds 4, 7, and 8 have also been determined by single-crystal X-ray diffraction analysis.